Transmission assemblies of various kinds for various work vehicles may include gears and associated components arranged to contact a fluid to dissipate heat and ease engagement of mating parts. Cooling is particularly important for certain heat-producing components (e.g., brakes, clutches and the like). Such transmission components (and others) may be configured or located (e.g., nested within other components) such that it may be difficult to adequately deliver the cooling fluid thereto. Cooling arrangements may also realize certain inefficiencies, such as inefficiencies associated with cooling heat-producing components when in non-operational or other states.